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How large can a mature Equisetum gametophyte become?

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Horsetail — Equisetopsida Giant horsetail of Europe (*Equisetum telmateia*).

A mature Equisetum gametophyte can reach a size of up to 3 centimetres (1.2 inches) in diameter. These gametophytes are described as delicate, green, and flattened structures that resemble miniature pincushions.1